Yes, I believe security was the primary reason it isn't included in HTML5. That said, I'm not sure exactly how it would function- it would be very bad if HTML was able to give a website liberal access to your HDD/SSD, cam, and mic without prior notification.

Fun fact: HTML6 (or what will essentially be HTML6) will have a [device] tag, that will be able to, in theory, comunicate with ANY device. (Controller, flightstick, camera, mic, HDD/SSD, rom drive, etc...)

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